Method and apparatus for circulatory valve repair

ABSTRACT

An apparatus for the repair of a cardiovascular valve has leaflets comprising a grasper capable of grabbing and co-apting the leaflets of the valve. In a preferred embodiment the grasper has jaws that grasp and immobilize the leaflets, and then a fastener is inserted to co-apt the leaflets. The apparatus is particularly useful for repairing mitral valves to cure mitral regurgitation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending, commonly assigned U.S.patent application Ser. No. 09/950,163, filed Oct. 15, 2002, which is acontinuation of, commonly assigned U.S. patent application Ser. No.09/747,558, filed Dec. 23, 2000 now abandoned, which is a continuationof, commonly assigned U.S. patent application Ser. No. 09/254,111, filedFeb. 25, 1999, now U.S. Pat. No. 6,269,819, which is a National Phaseof, commonly assigned PCT Patent Application No. PCT/US98/13240, filedJun. 25, 1998, which corresponds to U.S. Provisional Patent ApplicationSer. No. 60/051,078, filed Jun. 27, 1997, now abandoned.

FIELD OF THE INVENTION

The present invention relates generally to the field of circulatoryvalve repair. More particularly, the present invention relates to thefield of the repair of heart valves and specifically for the repair ofmitral heart valves, for patients suffering from mitral regurgitation.

BACKGROUND OF THE INVENTION

There are four valves in the heart that serve to direct the flow ofblood through the two sides of the heart in a forward direction. On theleft side, the mitral and aortic valves direct oxygenated blood comingfrom the lungs, through the left side of the heart, into the aorta fordistribution to the body. On the right side, the tricuspid valve,located between the right atrium and the right ventricle, and thepulmonary valve, located between the right ventricle and the pulmonaryartery, direct de-oxygenated blood coming from the body, through theright side of the heart, into the pulmonary artery for distribution tothe lungs. The anatomy of the heart and the structure and terminology ofheart valves are described and illustrated in detail in numerousreference works on anatomy and cardiac surgery, including standard textssuch as Surgery of the Chest (Sabiston and Spencer, eds., SaundersPubl., Philadelphia) and Cardiac Surgery by Kirklin and Barrett-Boyes,Pathology and Abnormalities of Heart Valves, incorporated herein byreference.

All four heart valves are passive structures in that they do notthemselves expend any energy and do not perform any active contractilefunction. They consist of moveable “leaflets” that are designed simplyto open and close in response to differential pressures on either sideof the valve. The mitral valve has two leaflets and the triscupid valvehas three. The aortic and pulmonary valves are referred to as “semilunarvalves” because of the unique appearance of their leaflets, which aremost aptly termed “cusps” and are shaped somewhat like a half-moon. Thecomponents of the mitral valve assembly include the mitral valveannulus; the anterior leaflet; the posterior leaflet; two papillarymuscles which are attached at their bases to the interior surface of theleft ventricular wall; and multiple chordae tendineae, which couple themitral valve leaflets to the papillary muscles.

The problems that can develop with valves can be classified into twocategories: (1) stenosis, in which a valve does not open properly, or(2) insufficiency, or regurgitation, in which a valve does not closeproperly.

Mitral regurgitation (“MR”) is caused by dysfunction of the mitralsubvalvular apparatus or direct injury to the valve leaflets. Multipleetiologies can lead to mitral regurgitation, with myxomatousdegeneration of the valve and ischemic heart disease accounting forclose to 60% of cases. Repair of the diseased valve requires majorsurgery on cardiopulmonary bypass to allow access to the valve.Consequently, some patients in the early or late stages of the diseaseare not considered appropriate candidates due to the high riskassociated with the operation. Multiple studies have demonstrated thatprosthetic replacement of the mitral valve can lead to significantpostoperative left ventricular dysfunction and often requires lifelongtreatment with anticoagulants. Mitral valve repair, using a posteriorannuloplasty ring, has demonstrated improved results with betterventricular recovery. Nevertheless, recent studies performed by theinventors (Umana et al., Surg Forum 1997) have revealed that posteriorring annuloplasty causes changes in ventricular geometry that lead toparadoxical movement of the normal papillary muscles, furtherdeteriorating ventricular performance. In contrast, the “bow-tie” repairin which the anterior and posterior leaflets of the mitral valve arefixed in opposition appears to enhance annular contractility whilepreserving ventricular architecture. This has resulted in improvedpostoperative ventricular function almost uniformly.

The present invention addresses the needs of all patients with mitralregurgitation without mitral stenosis, including those who heretoforemay have been excluded due to having only moderate MR or being too sickto be candidates for major surgery.

The present invention finds utility not only for the repair of mitralvalves but for all valves of the circulatory system, including aorticvalves, tricuspid valves, and venous valves.

Techniques for improving the efficacy of corporeal valves are known. Forexample, Laufer et al., U.S. Pat. No. 5,609,598 describes a valvingsystem for treatment of chronic venous insufficiency. The system hasinherent limitations in terms of its effectiveness for the proceduredescribed and its applicability, if any, to other valves, especiallycardiac valves.

SUMMARY OF THE INVENTION

The present invention is directed to a method and apparatus for use inheart valve repair involving the use of an inserted device or grasperfor grabbing and clasping together the anterior and posterior leafletsof the valve, by insertion into the left ventricle through the rightchest via a thorascope, through the jugular vein, or through the femoralartery. The grasper will grab both leaflets, preferably after the hearthas been stopped or slowed pharmacologically. The correctness of theinitial grasp is assessed by, for example, intraoperativeechocardiography, to ensure, for example, in the case of the mitralvalve, that the mitral regurgitation is resolved. If not, the grasperwill be able to “adjust” the leaflets to allow better coaptation or, ifneeded, re-grab the leaflets in a different location.

Either inherent to the grasper, as an integrally attached component oras a separate device, a fastening device is introduced and a fastener isdeployed to securely hold the leaflets in place after the grasper hasbeen released. The remaining portion of the device, or optionally anyseparate device, is then removed.

Accessory devices needed for the procedure include instruments forthoracoscopic or percutaneous approaches. While the preferred method andapparatus described hereinbelow is discussed with reference to its usein connection with mitral valve repair, it is contemplated that the sameor substantially similar apparatus and methodology would also be usefulin repairing other valves found in the human circulatory systems,particularly other heart valves, such as, for example, venous valves,aortic valves and tricuspid valves, amongst others.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a method for the repair ofheart valves to increase their efficiency.

It is a further object of the invention to provide for a method for therepair of mitral valves to reduce mitral regurgitation.

It is also an object of the invention to provide for a method for therepair of the mitral valves which eliminates the need forcardiopulmonary bypass surgery.

It is a further object of the invention to provide for an apparatus forpercutaneous insertion into the heart to effect the repair of a heartvalve.

It is a yet further object of the invention to provide for the repair ofa mitral valve by percutaneous insertion of a grasping and fasteningdevice into the heart to repair a mitral valve and reduce or eliminatemitral regurgitation.

These and other objects of the invention will become apparent to oneskilled in the art from the more detailed description given below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 4 are each a schematic representation of a portion of thehuman heart showing the mitral valve, the left ventricle and anapparatus of the invention in operation;

FIG. 5 is a schematic representation of an embodiment of the distalportion of an apparatus of the invention useful for grasping a mitralvalve;

FIG. 6 is a schematic representation of an embodiment of a distalportion of an apparatus of the invention showing a configuration of afastener holder and a fastener clip in the open position;

FIG. 7 is a schematic representation of an embodiment of FIG. 6 showingthe release and closure of the fastener clip;

FIG. 8 is a detailed, partly cross-sectional schematic representation ofthe distal end of a preferred embodiment of a grasper device accordingto the invention in the open position;

FIG. 9 is a detailed, partly cross-sectional schematic representation ofthe preferred embodiment of a grasper device according to the inventionshown in FIG. 8 in a closed position depicting the translocatedadjustable grasper and fastener anvil within the jaws;

FIG. 10 is a cross-sectional representation across line 10-10 of theadjustable grasper shown in FIG. 9;

FIG. 11 is a detailed schematic representation of a preferred embodimentof the grasper device of the apparatus of the invention in the closedposition with the integral closure means shown;

FIG. 12 is a detailed schematic representation of the preferredembodiment depicted in FIG. 9 showing the closure means piercing theleaflets of the valve;

FIG. 13 is a detailed, partly cross-sectional schematic representationof yet another preferred embodiment of the distal end of a grasperdevice according to the invention showing the use of a coil closuremeans;

FIGS. 14, 15, and 16 are partly cross-sectional schematicrepresentations of another embodiment of the invention, wherein aself-closing closure is used;

FIG. 17 is a schematic representation of the self-sealing closure;

FIGS. 18 and 19 are schematic representations of an embodiment of theinvention with a three-piece closure;

FIG. 20 is a schematic representation of an embodiment of the inventionwith a three-piece closure;

FIGS. 21 and 22 are oblique, schematic representations of a valveleaflet closure useful according to the invention;

FIG. 23 is a partial cross-sectional view of the closure shown in FIGS.21 and 22;

FIG. 24 is an oblique, schematic representation of another valve leafletclosure useful according to the invention;

FIG. 25 is a partial cross-sectional view of the closure in FIG. 24 inposition;

FIGS. 26 to 28 are each an oblique, schematic representation of a spiralcoil valve leaflet closure useful according to the invention;

FIG. 29 is an oblique schematic representation of a U-shaped valveleaflet closure useful according to the invention; and

FIG. 30 is a partly cross-sectional view of the closure shown in FIG.29.

DETAILED DESCRIPTION OF THE INVENTION

The invention can perhaps be better appreciated by making reference tothe drawings. In FIG. 1 a portion of the human heart is depicted showinga mitral valve 10, a left ventricle 12 and the distal end 14 of agrasper apparatus of the invention 16, which has been inserted throughan incision 18 in left ventricle 12. Incision 18 is loosely sutured withsutures 20 to loosely hold distal end 18 and to prevent bleeding.

Mitral valve 10 comprises anterior leaflet or cusp 22 and posteriorleaflet or cusp 24, as well as two commissural cusps (not shown). Theprimary intent of the invention herein is to secure the distal sections26 and 28 of cusps 22 and 24, respectively, together or substantiallyadjacent.

As can be seen in FIG. 2, the jaws 30 of distal end 14 are separated andpositioned exterior to cusps 22 and 24. Then, as shown in FIG. 3, jaws30 are clamped together to cause cusp distal sections 26 and 28 to cometogether. Once a closure is embedded, such as the loop closure 32 inFIG. 4, jaws 30 are opened slightly so that distal section 14 can bewithdrawn.

The distal ends of the grasper means can vary greatly. It iscontemplated that a variety of grasper means may be employed havingdiffering grasper configurations and elements. For example, it iscontemplated that the grasper means could be of the type wherein oneside of the grasper is stationary and the other side movable.Alternatively, the grasper means might be of the type wherein both sidesare movable in concert. Another alternative arrangement comprises agrasper means having multiple grasper elements to enable one to graspand hold the leaflets of the valve in multiple locations. It is alsocontemplated that the grasper elements themselves might comprise one ormore suction elements to secure and hold the valve leaflets in place.Preferably the grasper will have the capacity to adjust the leaflets of,for example, a mitral valve to obtain optimal coaptation.

In addition it is contemplated that the grasper may comprise additionaltechnology to facilitate the operation of the grasper. For example, thegrasper may have echo doppler probe or a similar visualizationtechnology that would allow even better localization of the leaflets andconfirmation of ideal coaptation.

FIG. 5 depicts the grasper end 36 of a percutaneous apparatus 38 withjaws 40 in the open position. Jaws 40 of grasper end 36 are movablyengaged about joint 42 such that the jaws may be easily and freelyopened or closed by the operator of the percutaneous apparatus.

Depicted in FIG. 6 is an embodiment of the invention showing onepossible configuration of a fastener holder 44 with a fastener clip 46in place held in the open position for placement over the graspedleaflets of a mitral valve. The fastener holder 44 and fastener clip 46may be integral with a grasper end as shown in FIG. 5 or separate fromit, in which case it will be necessary to also provide a secondarypercutaneous means for use in delivering and manipulating the fastenerholder 44 and releasing and fixing the fastener clip 46 in the properposition about the leaves of a mitral valve, once they have beenproperly grasped by jaws 40 of grasper end 36.

FIG. 7 is a more detailed schematic representation of the fastenerholder 44 with its jaws 48 in their open position and fastener clip 46in place in the open position (dotted line). Also shown is fastener clip46 in its released, closed position. Fastener clip 46, which may have aclosed diameter of from about 3 to 7 mm, preferably about 5 mm, will becomprised of a suitable material such as stainless steel, nitinol, ortitanium.

FIG. 8 depicts a detailed, partly cross-sectional schematicrepresentation of a preferred embodiment of the grasper device of thepresent invention, comprising grasper end 50, movable jaws 52 which aremovably engaged about joint 54, in the open position, in proximity tovalve leaflets 56. Each jaw 52 has a protruding grasping surface 58.However, the grasping surface 58 of one jaw 52 is operatively andslidably connected to a control member 60 to enable one to properlyalign valve leaflets 56, prior to fastening.

In FIG. 9 the grasper device of the apparatus of the invention shown inFIG. 8 is in a closed position. Moveable jaws 52 have protruding graspersurfaces 58, which engage valve leaflets 56. Leaflets 56 aretranslocated to a more optimum position for fastening by the action ofcontrol member 60 on one of protruding grasping surfaces 58, as shown inFIG. 11. Also, stapler action rod 68 is now operatively connected tostapler control member 70.

FIG. 10 is a schematic representation of a cross section of theadjustable grasper depicted in FIG. 9. The jaws comprise graspersurfaces 58, an upper anvil 62 with recess 71, and a lower anvil 64within which is located a staple type fastener 66 to effect thefastening of valve leaflets.

As shown in FIGS. 9, 11, and 12, lower anvil 64 has at least one slantedsurface member 72. When stapler action rod 68 is forced distally againstslanted surface member 72, stapler fastener 66 is forced throughleaflets 56 into upper anvil 62 to close stapler fastener 66.

In another embodiment of the invention shown in FIG. 13, a grasper 80comprises jaws 82, 84. Jaw 82 is movably connected to rod 86 at pivotpoint 87, and jaw 84 is movably connected at pivot point 88 to rod 90.Rod 92 is movably connected to jaw 84 at pivot 94. Operation of rods 90and 92 causes jaws 82 and 84 to open and close on valve leaflets 96.Axial to grasper 80 is a sheath 98 containing a drive mechanism 100 forrotating coil fastener 102. Coil fastener 102 advances in a spiral modepiercing leaflets 96 in multiple locations as coil 102 is advanced intoits final position.

Rods 86, 90, and 92 are each operatively connected to one or morecontrol mechanisms (not shown). Also, distal section jaws 82,84 may beslidable within grasper sheath 81.

Another device 110 of the invention is shown in FIGS. 14 to 16, wherejaws 112 are operatively connected to a handle mechanism (not shown).Device 110 comprises a movable sheath 114 that contains a straightenedclosure fastener 116 that is capable of resuming or forming a circularshape to coapt valve leaflets (not shown). Device 110 has a slidablyextruding grasping surface 118 that is operatively connected to thehandle mechanism.

Once jaws 112 are closed, the distal tip of sheath 114 is advanceddistally to be adjacent grasping surface 118 and its cooperatinggrasping surface 122. A pusher 124 coerces fastener 116 to advance outof the distal end 126 of sheath 114 to form a circular shape. Fastener116 in this shape will coapt valve leaflets 120, as can be seen in FIG.17.

The device 130 of the invention shown in FIGS. 18 and 19 is intended toform a three-piece closure device. Jaws 132 each removably hold aclosure member 134 having a grasping surface 136. Located axially withdevice 130 is a closure crimper 138 that is removably fastened at thedistal end 140 of a device rod 142. When jaws 132 grasp valve leaflets144, closure crimper 138 is advanced distally by device rod 142 to fitover the proximal ends of closure members 134. The closure formed isshown in FIG. 20.

While a typical grasper means configuration would normally require theuse of at least one control wire to actuate the grasper element(s), itis contemplated that multiple separate control wires could also beeffectively employed and manipulated from the proximal end of the systemto allow for the precise control of the individual grasper elements.

With regard to the fastening means employed, as noted above it iscontemplated that the fastening means may be constituted as a singleapparatus operating in concert with the grasper means. Alternatively,the fastening means may be constituted as an entirely separate devicewhich is totally independent of the grasper means. More preferably thefastening means will be a separate device which will function using amonorail type system, wherein the fastening means will operateindependently of the grasper means, but will ride via a loop over thesame guidewire/catheter which houses and guides the grasper means.

While the preferred fastener depicted is in the form of a clip orstaple, it is also contemplated that the fasteners employed to securethe leaflets of the valve may be of a variety of differentconfigurations, each of which would function with greater or lessereffectiveness depending upon the operative conditions which prevail. Inaddition to clips or staples it is also contemplated that the followingtypes of fasteners may also be effectively employed: coils, sutures,dual button fasteners, cufflink-like fasteners, and the like.

Suitable suture fasteners would include those which might require anappropriate mechanism to automatically suture tissue. Coil fastenerswould generally be provided with sharpened ends to allow one to screwthese fasteners into place by threading the sharpened end through thetissue of the valve leaflet.

With reference to FIGS. 21 to 23 which depict a sequentialrepresentation of the closure of valve leaflets using one preferredclosure means, shown in FIG. 22 is a clip type closure 150 beinginserted through valve leaflets 152. FIG. 22 shows the clip type closure150 in the fastened position. FIG. 23 is a cross-sectional view of theclip type closure 150 depicted in FIG. 23. Each closure 150 as shown inFIG. 21 would have a thickness of from about 0.5 to 1.8 mm, preferablyabout 1 mm, a width of from about 0.3 to 0.7 cm, preferably about 0.5cm, and a length of from about 0.6 to 1.4 cm, preferably about 1 cm.

FIGS. 24 and 25 are each a schematic representation of the insertion ofanother preferred closure means of the invention. A staple-type closure156 is inserted through valve leaflets 158, and then closed, as shown inFIG. 26. Closure 156 would preferably have an overall length (includingsides) of from about 1 to 4 cm, preferably about 3 cm, an effectivediameter of from about 0.1 to 0.5 mm, preferably about 0.3 mm, and anopening of from about 0.5 to 1.3 cm, preferably about 1 cm.

FIGS. 26 to 28 are each a schematic representation of the insertion ofyet another preferred closure. A spiral coil closure 160 can be insertedacross valve leaflets 162 in longitudinal, latitudinal, or transversefashion, by use of, for example, the device shown in FIG. 13. Coils 160will preferably have pointed ends and will have external dimensionscomprising a length of from about 3 to 7 cm, preferably about 5 cm, anda diameter of from about 1 to 3 mm, preferably about 2 mm.

The overall diameter and/or the differential turns of coil 160 may beuniform or they may vary. For example, the diameter at each end of coil160 could be the same as, greater than, or less than the diameter of themiddle portion of the coil. Similarly, the ratio of the turns of thecoil to the length, i.e., the pitch, could be consistent or the pitchcould be greater or less at each end of the coil. The diameter of thecoil wire will preferably be consistent.

Each coil 160 would have a length of from about 3 to 7 cm, preferablyabout 5 cm, with a diameter of from about 1 to 3 mm, preferably about 2mm, and a coil wire diameter of from about 0.2 to 0.4 mm. The winding ofcoil 160 should be from about 5 to 10 turns/cm in an unstressedcondition.

In FIGS. 29 and 30 a U-shaped barbed clip-type closure 164 is applied toleaflet 166.

The device and fasteners used according to the invention must becomprised of biocompatible, nonimmunogenic materials. The grasper ispreferably comprised of rigid materials such as titanium, nitinol,stainless steel, or rigid polymeric material such as polyethylene orpolyurethane. The clips, staples, coils, etc., are preferably comprisedof titanium, nitinol, or stainless steel. In some instances fastenerscomprised of molded polymeric material may also be useful.

There are four different approaches which one might take to effect arepair of the mitral heart valve according to the invention:

Such a procedure might be undertaken while the patient is on by-passwith an open-chest, either transapically or transatrially. A mediansternotomy is performed and the patient is placed on cardiopulmonarybypass by cannulating the ascending aorta and the right atrium. Apurse-string suture is then placed on the apex of the left ventricle anda stab incision performed to insert the instrument which will grasp andattach the mitral valve leaflets. Once adequate repair of the valve isattained, the instrument is removed and the air evacuated from the leftventricle through the apical incision. The ventricle is then repairedusing conventional wound closure techniques.

Alternatively, the grasper can be introduced through a similar stabincision performed over the roof of the left atrium. The grasper willcross the valve and then be manipulated to revert to grasp the leafletsfrom the atrial side and place the suturing device, just as postulatedfrom the transventricular approach. Once adequacy of repair isconfirmed, the device is extracted and the atriotomy closed usingconventional wound closure techniques.

This procedure can alternatively be performed with the patient offbypass, through either a left or right thoracotomy or a sternotomyincision. The technique would be similar to that outlined for repair ofmitral regurgitation on cardiopulmonary bypass. After opening the chest,the patient is placed on medication (beta-blocker) to slow the heartrate to approximately 40 beats per minute. This allows adequateechocardiographic visualization of the leaflets in order to grasp andattach them.

Third, such a procedure can be undertaken thorascopically. The patientis intubated selectively in order to collapse the left lung, andpercutaneous ports are inserted in to the left chest allowingvisualization of the apex of the heart or left atrium. Through aseparate port, the device is introduced into the thoracic cavity andsubsequently into the left ventricle through the apex. Previously, apurse-string or triangular suture had been placed around the tip of theventricle to control bleeding around the ventricular entry site.Subsequent steps of the repair are identical to those described forpatients with an open chest, off bypass.

Should the operation require the patient to be placed on bypass, thiscan be attained percutaneously from the groin by cannulating the femoralartery and vein. This technique could prove particularly useful in theearly stages of development of the technique, since the surgeon would beable to operate on a decompressed heart and slow or cease the heart rateas needed, without hemodynamic compromise.

Lastly, a percutaneous approach to repair of the mitral valve would bepossible with this invention by inserting the device either through thefemoral artery or jugular vein. When using the former, the leftventricle is reached by placing the device across the aortic valve. Theleaflets will be grasped by turning the tip of the instrumentapproximately 160° from the entry angle. As previously stated, thegrasper's tips are adjusted to obtain optimal apposition and thesuturing device delivered. If a transvenous approach is employed, theleft atrium is entered through the interatrial septum and the leafletsare handled as described for the transatrial technique.

To determine the relative efficacy of the method of the invention ineffecting the repair of heart valves such as mitral valves a number ofprocedures were performed on both animal and human test subjects asfollows:

Animal Testing

Six adult sheep underwent ligation of OM2 and OM3 through a leftthoracotomy to induce chronic ischemic MR. After 8 weeks, animals wereplaced on cardiopulmonary bypass. Using a posterior approach to the leftatrium, a bow-tie repair was performed. A posterior suture annuloplasty(DeVega) served as control. Snares were placed on both repairs to allowalternate tightening during measurements. Ten 2-mm piezo-electriccrystals were sutured around the MV annulus and at the bases and tips ofthe papillary muscles. Six crystals were secured to the apex (1), septum(1), and epicardial short axis of the left ventricle (4) for3-dimensional sonomicrometry array localization (3D-SAL) imaging. 3D-SALmeasurements were performed after weaning from cardiopulmonary bypass atbaseline and with each type of repair. Echocardiography was used tomeasure MR, MV area, and fractional shortening.

TABLE 1 MR, mitral valve area, and fractional shortening MR FS MVA (cm²)Baseline 3.3 0.46 5.4 DeVega 1.4 0.53 3.9 Bow-tie 1.2 0.57 3.3 FS =fractional shortening; MVA = mitral valve area (planimetry). *P = 0.0159vs. baseline **P = 0.0079 vs. baseline

As shown from the results presented in Table 1, MR decreasedsignificantly with both repairs compared with baseline. Post-operativeimprovements in fractional shortening was greater in the bow-tie groupbut did not reach statistical significance. MVA, measured by planimetry,decreased more with the bow-tie repair; nevertheless, the resultantareas were still substantial without evidence of a transvalvulargradient. Mitral valve annular contractility (% area change=(maximumarea−minimum area)/maximum area) by 3D-SAL increased from 19.7%±4.0% atbaseline to 21.5%±3.2% after bow-tie repair (P=0.026). Sutureannuloplasty decreased annular contractility to 15.7%±3.6% (P=0.0011 vs.baseline, and P=0.0001 vs. bow-tie).

The results obtained suggest that current techniques of mitral valverepair in ischemic MR may further impair left ventricular performance bylimiting systolic function of the annulus and base of the heart. Thebow-tie repair technique which is the subject of the present inventioncontrols MR and directly addresses subvalvular dysfunction resulting inimproved annular and left ventricular function.

Human Testing

The charts of eleven patients (five males and six females) undergoingmitral valve repair in conjunction with a central leaflet suture(“bow-tie” repair) were reviewed. Patients were operated on betweenAugust 1996 and April 1997. Mean age was 68 years (range, 44 to 78).Etiology of mitral regurgitation (MR) was ischemic in nine patients anddegenerative in two. Mitral regurgitation was attributed to ischemia ifany of the following criteria proposed by Radford et al. was met: (1)rupture of a papillary muscle chord or head (n=3); (2) infarction of thepapillary muscle in the absence of leaflet pathology (n=3); (3) clearhistory of new onset or worsening of mitral regurgitation afterdocumented myocardial infarction (n=3).

The diagnosis of MR was established by echocardiography in 10/10patients, and semiquantitatively graded as severe (4+), moderate/severe(3+), mild/moderate (2+), mild (1+), and trace. Left sided cardiaccatheterization confirmed the presence of MR in nine patients and thepresence of critical coronary artery disease (CAD) invariably involvingthe circumflex and posterior descending artery territories in allpatients with ischemic MR. Preoperative diagnoses and hemodynamicsobtained during catheterization are shown in Table 2. All patients werein NYHA class III or IV at the time of surgery.

TABLE 2 Preoperative diagnosis and hemodynamics. Patient Diagnosis AgeCO PCWP v-wave 1 Unstable angina 59 4.2 30 80 2 CAD/torn post. chord 782.4 6 10 3 CAD 74 n/a 14 15 4 CAD/MIx3 64 n/a n/a n/a 5 Unstableangina/MIx2 44 4.0 26 41 6 Ischemic VSD 77 4.0 28 21 7 AI/MR 77 4.5 2939 8 CAD/APM rupture 67 4.3 27 65 9 CAD/V-tach arrest 71 4.1 20 28 10Degenerative MR 70 3.5 20 21 11 AMI/PPM rupture 67 4.1 33 60AI-aortic insufficiency; AMI-acute myocardial infarction; APM-anteriorpapillary muscle; CAD-coronary artery disease; post-posterior;PPM-posterior papillary muscle; VSD-ventricular septal defect;v-tach-ventricular tachycardia

With the patient under anesthesia, the valve is visualized ontransesophageal echocardiogram (TEE) and the likely mode of failuredetermined, with special emphasis on the presence of leaflet prolapseand site and direction of the regurgitant jet. After the heart wasstopped, a bulb syringe with cold saline is used to distend the leftventricle and confirm the mode of valve failure. A conventional repairusing an annuloplasty right is generally performed and the valve isreinspected with saline injection. If the leaflet edges do not opposeeach other in a concentric circle parallel to the annuloplasty ring, andcontinued regurgitation is observed, then a “bow-tie” repair isinitiated. If the repair is performed from the transventricular ortransaortic exposure, a single figure of eight 4-0 prolene suture isplaced without screening leaflet eight 4-0 prolene suture is placedwithout screening leaflet-coaptation. Using a 4-0 prolene suture, theanterior leaflet is attached to the corresponding posterior leaflet atthe site of malapposition. The figure of 8 suture is placed through eachleaflet just as the edge turns down to attach to the primary chordae.This is usually the most cephalad site where the 2 leaflets would touchduring systole and creates the largest area of coaptation possible.

At time the suture is very close to a commissure and the result is anarrowing of single valve orifice. More commonly, the suture is closerto the center of the valve and a double orifice valve is created whichresembles a “bow-tie”. After visually confirming that the repair issatisfactory with cold saline injection, the atrium is closed, thepatient weaned from CPB, and an intraoperative TEE used to confirm theadequacy of the repair. Standard as well as exercise transthoracicechocardiograms were performed prior to discharge to establish thecompetency of the “bow-tie” repair as well as the absence of asignificant gradient across the valve.

Six patients were operated on electively for worsening MR leading tointractable congestive heart failure or unstable angina. Four patientsunderwent emergent operation due to acute worsening of MR secondary toischemic anterior papillary muscle rupture (n=2), acute MI withcardiogenic shock requiring intraaortic counterpulsation balloon, severeMR and malignant arrhythmias (N=1), and acute worsening of chronicdegenerative MR (n=1). One patient had moderate (3+0 MR in associationwith critical aortic insufficiency. Mean degree of preoperative MR byecho was 3.5±0.7, with mean ejection fraction (EF) of 42%±17%. Ninepatients underwent preoperative cardiac catheterization. Mean pulmonarycapillary wedge pressure was 23 mmHg±8 mmHg, with mean atrial v-wave of39 mmHg±25 mmHg; mean CO as measured by thermodilution technique was 3.91/min (range 2.4 to 4.5 1/min) (Table 2). Concomitant proceduresperformed at the time of MR included coronary artery bypass grafting(CABG) in eight patients. Of the two patients with a degenerativeetiology of valvular disease, one required aortic valve replacement,whereas the second underwent posterior leaflet quadrangular resectionand annuloplasty. Two patients, not included in this series, withend-stage congestive heart failure (CHF) secondary to ventriculardilation had “bow-tie” repairs during partial left ventriculectomy. Ninepatients had a posterior ring annuloplasty as primary procedure fortreatment of MR (Table 3). One patient required repair of ischemicventricular septal defect (VSD) through a ventriculotomy, which madeinsertion of an annuloplasty ring impractical. This patient's mitralvalve was successfully repaired with a “bow-tie” alone. A second patientpresented with acute MR secondary to rupture of the anterior head of theppm. Repair of the papillary muscle was performed using pericardialpledgets. Due to the lack of annular dilatation and persistence of MR a“bow-tie” suture was placed without an annuloplasty ring. Control of MRassessed intraoperatively by direct cold saline injection and TEE wassatisfactory in all patients.

TABLE 3 Operative indications and concomitant procedures PatientOperative indication Other procedures 1 MR, unstable angina CABG, C-E#282 Torn post chord, MR Post quad resection, C-E #32 3 CAD, MR CABG,C-E#32 4 CAD, MR CABG, C-E#30 5 Unstable angina, MR CABG, C-E#28 6Ischemic VSD, MR CABG 7 Critical AI, MR AVR, C-E#30 8 CAD, ALM rupture,MR CABG, C-E#26 9 CAD, MR CABG, C-E#28 10 MR, CHF C-E#30 11 PPM rupture,MR CABG, primary PPM repair AVR-aortic valve replacement; C-E Cosgrovering; CHF congestive heart failure; PPM posterior papillary repairAVR-aortic valve replacement; C-E Cosgrove ring; CHF congestive heartfailure; PPM posterior papillary muscle

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the constructions set forth withoutdeparting from the spirit and scope of the invention, it is intendedthat all matter contained in the above description and shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

DRAWING COMPONENTS No. Component 10 mitral valve 12 left ventricle 14distal end of grasper 16 grasper 18 incision 20 suture 22 anteriorleaflet or cusp 24 posterior leaflet or cusp 26 anterior cusp distalsection 28 posterior cusp distal section 30 jaw 32 closure loop 36grasper end 38 percutaneous apparatus 40 jaw 42 joint 44 fastener holder46 fastener clip 48 jaw 50 grasper end 52 jaw 54 joint 56 valve leaflet58 protruding grasping surface 60 control number 62 upper anvil 64 loweranvil 66 staple type fastener 68 staple action rod 71 recess 72 anvilslanted surface 80 grasper 81 grasper sheath 82 jaw 84 jaw 86 rod 87pivot point 88 pivot point 90 rod 92 rod 94 pivot 96 valve leaflet 98sheath 100 drive mechanism 102 coil fastener 110 grasper device 112 jaw114 sheath 116 fastener 118 grasping surface 120 leaflet 122 cooperatinggrasping surface 124 pusher 130 grasper device 132 jaw 134 closuremember 136 grasping surface 138 closure crimper 140 rod distal end 142device rod 144 valve leaflet 150 clip-type closure 152 valve leaflet 156staple-type closure 158 valve leaflet 160 spiral closure 162 valveleaflet 164 barbed-clip closure 166 valve leaflet

1. A method for approximating and fastening cardiac valve leaflets, saidmethod comprising capturing the valve leaflets between two clippingelements, wherein the valve leaflets are fastened together, wherein oneof said clipping elements has a longer surface in contact with theleaflets than does the other clipping element, and wherein the clippingelements are deployed on the leaflets and left in place afterdeployment.
 2. A method as in claim 1, wherein the clipping elementsengage the leaflets with barbs.
 3. A method as in claim 1, wherein theclipping elements are arranged as a U-shaped clip.
 4. A method as inclaim 1, wherein clipping elements are inserted into the heart throughthe chest via a thorascope.
 5. A method as in claim 1, wherein theclipping elements are inserted through the vein.
 6. A method as in claim1, wherein the clipping elements are inserted through the femoral arteryand advanced percutaneously.
 7. A method as in claim 1, wherein thecardiac valve is a mitral valve or an aortic valve.
 8. A method as inclaim 7, wherein the cardiac valve is a mitral valve.
 9. A method as inclaim 7, wherein the cardiac valve is an aortic valve.
 10. A method asin claim 1 or 7 for repairing a mitral valve in a patient suffering frommitral valve regurgitation wherein the leaflets of the mitral valve arecaptured and the clipping elements are closed over the captured mitralvalve leaflets to coapt the leaflets.
 11. A method as in claim 1 forrepairing an aortic valve in a patient suffering from aortic valveinsufficiency wherein the leaflets of the aortic valve are captured andthe clipping elements are closed over the captured aortic valve leafletsto coapt the leaflets.